Yes, I was referring to pictures in general. The audio describes the need to get the left arm, clubshaft and especially right forearm their impact fix alignment at impact. This would be done through the pressure points. Again, I believe his focus was on how the pressure points allow the club head to be properly released. From the looks, and again, we're past follow through, I think it's a strong single grip, but with vertical (maybe angled) hinging.
Hope this helps - it is hard to tell from that position, but I've watched these videos many times (as everyone has) and I don't remember any discussion of grip beyond strong single.
I think the idea of delivering the entire lever assembly into impact together is the whole idea with regard to clubhead 1-L-8.
However, I would not emulate the hinge action shown - The more I look, it is a vertical hinge action and therefore clubface manipulation.
I would do this:
Work to bring the entire lever assembly to release, and if using standard wrist action, use the impact swivel to bring you into impact. Then using your choice of hinge action, move to follow through (both arms straight).. THEN, employ the follow through swivel to bridge between followthrough and finish.
The picture at the top is well past followthrough so therefore, is not accurate, but is describing the lever assembly being to and through impact with a flat left wrist.
I would youtube some of Lynn's or any swing vision tour swing and you'll see the
sequencing of #2 and the #3 accumulator releases.
So, I think it's an abberation!! I'll leave agnostic to you....